Aluminum methionate



Patented Apr. 18, 1950 ALUMINUM METHIONATE John Edward Christian andGlenn L. Jenkins, La Fayette, Ind., assignors to Purdue ResearchFoundation, a corporation of Indiana No Drawing. Application October 4,1946,

Serial No. 701,091

1 Claim. 1

This invention relates to new astringent agents, the preparation of suchagents and to cosmetic anti-perspirants including them.

Up to the present time the conventional antiperspirants have been saltsof weak metals, such as aluminum, with strong inorganic acids, such ashydrochloric and sulfuric. The usually employed compounds have beenaluminum chloride and aluminum sulfate, although zinc, thorium and othermetal salts have been known to be equivalent. These astringent salts ofweak metals and strong acids are effective in reducing perspiration, butby themselves are corrosive to clothing and may cause skin irritation.While this corrosion may be inhibited, the inhibitors are relativelyexpensive.

We have now discovered that certain organic salts of weak metals, suchas aluminum, are effective anti-perspirants but are harmless to skin andfabrics. The preferred member of the group is aluminum methionate, oraluminum methane disulfonate having the formula:

80: (C: )IAh 501 Other aluminum alkyl sulfonates are likewise effectiveas anti-perspirants. Aluminum methionate, aluminum ethane disulfonateand aluminum methane trisulfonate are considered the most activeastringents of those prepared and tested.

The compositions appear to require the following three characteristics:

(1) The aluminum ion or its equivalent.

(2) One or more sulfo groups.

(3) An alkyl group.

In general, the more sulfo groups, the greater is the astringency andthe fewer the carbon atoms in the alkyl groups, the greater is theastringency.

Aluminum methionate may be prepared as follows:

100 gm. of calcium methionate is dissolved in 250 cc. of warm water and102 gm. (98% of theory) of crystalline aluminum sulfate, dissolved in250 cc. of water, is added slowly with stirring. The mixture is digestedfor ten minutes, filtered, and the calcium sulfate washed with water,the water being added to the original filtrate. The filtrates may beconcentrated and aluminum methionate solution used as such. The puresalt may be isolated as follows: The aluminum methionate solution isconcentrated until a super saturated solution is obtained. A1-

cohol is added and the aluminum salt crystallizes out. The salt may befurther recrystallized from water and alcohol.

Aluminum methionate is hygroscopic and, therefore, does not tend to dryout. It does not tend to crystallize out of astringent creams. It issoluble in water and may be included in concentrations as high as 25 percent. I

Aluminum ethane disulfonate having the structural formula may beprepared by dissolving 5 gm. of barium ethane disulfonate in 200 cc. ofhot water and slowly adding 3 gm. of theory) of A12(SO4)3. 18 H2Odissolved in 10 cc. of water with stirring. The barium sulfate formed isilltered off. The filtrate is evaporated to about 10 cc. and ethylalcohol added to precipitate the aluminum salt. The salt is filtered,washed with water, and dried.

Aluminum methane sulfonate having the structural formula may be preparedby reacting methane sulfonic acid and aluminum sulfide.

57 gm. of methane sulfonic acid is placed in a suitable flask containing15.5 gm. (5% excess) of aluminum sulfide. Distilled water is added inexcess and the mixture heated on an electric hot plate and allowed toreact until no more H28 was evolved. The excess aluminum sulfide isfiltered off and the filtrate concentrated almost to dryness. Theproduct is allowed to crystallize and then washed with acetone to removethe remaining water present.

Aluminum methane trisulfonate having the structural formula may beprepared by reacting the barium salt with aluminum sulfate in the samemanner described in connection with the aluminum ethane disulfonate.

Aluminum sulfo-acetate having the structural formula Solc2-O O 0- Allmay be prepared by reacting the barium salt with aluminum sulfate in thesame manner described 3 in connection with the aluminum ethanedisulfonate.

Aluminum o-sulfo-benzoate having the structural formula "Iegacid"regular pounds 20 Stearic acid do 4 White protopet do /2 Distilled waterdo 35 Glycerlne -do- 1 Gum tragacanth owder do Aluminum methionate (71-/1% Sol.) do 33% Formaldehyde (37% solution) do Perfume ounces 3 Tegacidis the trade name for a mixture of glyceryl monostearate and a wettingagent presumably of the sulfated fatty alcohol compound type. Whiteprotopet is white petrolatum, U. 8.59.

4 We claim: As a new composition of matter, aluminum methionate.

JOHN EDWARD CHRISTIAN GLENN L. JENKINS.

REFERENCES CITED The following references are of record in the file ofthis :patent:

UNITED STATES PATENTS Number Name Date 59,239 Lewis Oct. 30, 18661,438,101 Divine Dec. 5, 1922 2,145,583 Carlson Jan. 31, 1939 2,236,387Wallace et a1 Mar. 25, 1941 2,316,670 Colgate et al Apr. 13, 19432,430,815 Hersberger et al. Nov. 11, 1947 FOREIGN PATENTS Number CountryDate 354,443 Great Britain of 1931 568,209 Germany Jan. 23, 1933 OTHERREFERENCES Drug and Cosmetic Industry, July 1937, vol. 41, page 117.

Beilstein, Handbuch der Org. Chem, vol. 4, (4th Ed. 1922) page 11.

Beilstein, Handbuch der Org. Chem, vol. 4, first Supplement (4th Ed.1929) page 310.

Chemical Abstracts, Abstracts of four publications by Becker et al., atthe following pages: vol. 24, page 82-8 (1930), vol. 25, page 915(1931), Vol.26, page 962 (1932) (two articles).

